Data is usually exchanged digitally between a graphics card in a personal computer and an LCD display module. The personal computer transfers digital R, G, B video signals to the LCD display module via a special so-called DVI (Digital Video Interface) cable, which comprises a circuit pair for each R, G and B channel. This DVI cable is also provided with further circuit pairs particularly for transmitting a DVI clock signal and for transmitting so-called DDC (Display Data Channel) data. This DDC circuit pair allows the personal computer and the LCD display module to communicate serially, with particularly specification information of the LCD display module, for instance information about data transmission rates, resolution of the LCD display or synchronization frequency, being transmitted via a data line and a DDC clock signal being transmitted via a clock line.